Surface material and method of manufacturing the same

ABSTRACT

To provide a surface material comprising main surfaces which are excellent feeling in touch and hardly cause fiber dropouts, and to provide a method for producing the same. In a surface material comprising binder and a monolayer fabric, it was found that a surface material satisfying both of the following configurations is a surface material with main surfaces which are excellent feeling and hardly cause fiber dropouts
         a configuration that there is no layer of binder on both main surfaces in the fabric, and,   a configuration that there are one or more layers of binder between both main surfaces in the fabric. In addition, a method of manufacturing a surface material comprising a step of applying the solvent and/or the dispersion medium to the one main surface, to which the binder liquid is applied, of a monolayer fabric, the binder liquid applied to the main surface can be pushed from the one main surface to the inner side of the monolayer fabric by a solvent and/or a dispersion medium so that the binder liquid does not exist on the one main surface. Therefore, a surface material satisfying the constitution of claim  1  can be manufactured.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to Japanese Patent Application No. 2019-230801, filed on Dec. 20, 2019, and to Japanese Patent Application No. 2020-202587, filed on Dec. 7, 2020, the entire contents of both of which are hereby incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a surface material and a method of manufacturing the same.

BACKGROUND ART

Conventionally, as a surface material capable of constituting an interior of an automobile or the like, the surface material comprising binder and a monolayer fabric is used, wherein fibers constituting a main surface of the surface material (said main surface derived from the monolayer fabric) are bonded and fixed by one or more layers of said binder. Then, the interior material is manufactured by heating and molding the surface material into an intended shape.

Applicant proposed JP 562-257472A (Patent Document 1) as a surface material of the above-described configuration, described in an interior skin material manufactured through the process of: subjecting to needle punch process on one side of the fibrous web, applying binder to the surface of the fibrous web subjected to the needle punch treatment, calendering, subjecting a tack small binder to an opposite surface of the fibrous web subjected to the needle punch treatment.

CITATION LIST Patent Literature

[Patent literature 1] JP 562-257472A

However, a layer of a binder is present on a main surface (the main surface derived from a monolayer fabric) of a surface material according to the prior art, and a fiber portion exposed on the main surface is bonded and fixed by one or more layers of the binder so that the main surfaces has bad feeling that a person does not feel raised feeling.

On the other hand, to provide a surface material with a main surface whose a person feels excellent feeling of touch when a binder is not applied to the main surface (the main surface derived from a monolayer fabric), a problem occurs that fibers tends to fall off from the main surface.

SUMMARY OF INVENTION Technical Problem

The purpose of the present invention is to provide a surface material comprising the main surfaces which are excellent in touch and hardly cause falling off of fibers, and a method of manufacturing the same.

Solution to Problem

The first invention is “A surface material comprising a binder and a monolayer fabric, the monolayer fabric having a first main surface and, on a side opposite the first main surface, a second main surface, wherein one or more layers of said binder are present only in an inner side of the first main surface of said monolayer fabric and only in an inner side of the second main surface of said monolayer fabric”.

Further, a second invention is “A method for manufacturing a surface material according to claim 1, comprising:

(1) preparing a monolayer fabric, (2) preparing a binder liquid comprising a binder and a solvent and/or a dispersion medium for the binder, (3) applying the binder liquid to one main surface of the monolayer fabric, (4) applying the solvent and/or the dispersion medium to the one main surface of the monolayer fabric, and (5) removing the solvent and/or the dispersion medium from the monolayer fabric”.

Advantageous Effects of Invention

As a result of the present applicant's examination, in a surface material comprising a binder and a monolayer fabric, it was found that a surface material satisfying both of the following configurations is a surface material with main surfaces which are excellent in feeling and hardly cause fiber dropouts:

-   -   a configuration that there is no layer of binder on both main         surfaces in the fabric, and,     -   a configuration that there are one or more layers of binder         between both main surfaces in the fabric.

In other words, in the surface material of the present invention, one or more layers of the binder are not present on both main surfaces of the monolayer fabric constituting a surface material. Therefore, since the fiber portions exposed on both main surfaces are not fixed by a layer of binder, both main surfaces make people feel raised feeling and have an excellent tactile sensation.

On the other hand, since one or more layers of the binder is present between both main surfaces in the fabric constituting the surface material, the portion of the fiber, that are exposed on each main surface and contribute to improving the tactile sensation, in the inner side of the fabric is bonded and fixed by the layer of binder. Therefore, the fibers, that are exposed on each main surface and contribute to improving the tactile sensation, do not easily fall off from each main surface.

Further, a method of manufacturing a surface material according to the present invention includes, after applying a binder liquid to one main surface of the prepared monolayer fabric, “(4) a step of applying the solvent and/or the dispersion medium to the one main surface of the fabric”. In this step, the binder liquid present on one main surface of the fabric can be moved from the main surface to the inner side of the fabric by then applying the solvent and/or dispersion medium containing no binder, so that there is no binder liquid on the main surface. Thereafter, by removing the solvent and/or the dispersion medium present in the fabric, a surface material satisfying the configuration according to claim 1 can be produced.

From the above, according to the present invention, it is possible to provide a surface material comprising main surfaces which are excellent in touch and hardly cause falling off of fibers.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.

FIG. 1 It is a schematic sectional view of a surface material according to the present invention.

FIG. 2 An optical micrograph of a sectional view of the surface material prepared in Comparative Example 1.

FIG. 3 An optical micrograph of a sectional view of the surface material prepared in Comparative Example 2.

FIG. 4 An optical micrograph of a sectional view of the surface material prepared in Example 1.

FIG. 5 An optical micrograph of a sectional view of the surface material prepared in Example 2.

FIG. 6 An optical micrograph of a sectional view of the surface material prepared in Example 3.

DESCRIPTION OF EMBODIMENTS

In the present invention, various configurations such as, for example, the following configurations can be appropriately selected. Note that various measurements described in the present invention were measured under atmospheric pressure unless otherwise specified. Further, various measurements described in the present invention were measured under 25° C. temperature conditions unless otherwise described. Then, unless otherwise stated, various measurement results explained in the present invention were obtained by measurement a value that is one order smaller than the desired value, and the obtained value was rounded to the nearest number to the obtained value. As a specific example, in the case where the 1st decimal place is the desired value, the 2nd decimal place is obtained by measurement, then the 1st decimal place is calculated by rounding off the obtained value of the 2nd decimal place, and this value is used as the value to be obtained.

The surface material of the present invention will be described with reference to FIG. 1, which is a schematic cross-view of the surface material according to the present invention. Note that the surface material (10) exemplified in FIG. 1 is a surface material (10) composed only of a monolayer fabric (1) and a binder layer (2). The surface material (10) of the present invention includes a monolayer fabric (1) and one or more layers of binder (2).

Here, the monolayer fabric (1) is a member mainly responsible for forming a skeleton of the surface material (10). Then, one or more layers of binder (2) serve to bond and integrate the constituent fibers of the monolayer fabric (1), to prevent the shape of the monolayer fabric (1) from unintentionally deforming and/or to improve various physical properties such as rigidity of the monolayer fabric (1). Further, it is possible to carry an additive as described later on the surface of the monolayer fabric (1) and in the void.

The fabric referred to in the present invention is a sheet-like fiber aggregate such as, for example, a fiber web, a nonwoven fabric, a woven fabric or a knitted fabric.

In addition, said “monolayer” referred to in the present invention means that the fabric is not a laminate of a plurality of fiber aggregates. Since the fabric has a monolayer structure, it is possible to provide a surface material (10) which hardly causes delamination in the fabric and is excellent in moldability when the fabric is heated and molded to produce an interior material.

Further, since the fabric has a monolayer structure, the type of the constituent fibers on one main surface of the fabric and the type of the constituent fibers on the other main surface can be made the same. Therefore, when the interior material is manufactured by heat molding, the followability to the mold on both main surfaces of the fabric becomes uniform, so the surface material (10) excellent in the molding property can be provided.

In contrast to the present invention, for example, in the case where two fiber webs having a binder layer on each one main surface are prepared wherein two fiber webs are bonded and integrated by the binder in a state where the binder layers face each other, or in the case wherein a surface material is prepared by performing an entanglement treatment such as a needle punching treatment on two fiber webs in a state where the binder layers face each other, a surface material having almost the same configuration as the present invention except that having a laminated structure, can be prepared. However, if the surface material is heat-molded to produce an interior material, delamination may easily occur.

As the reason for this, it is considered that due to the presence of the binder layer, the layer between the fiber webs is weakly entangled with the constituent fibers, so that the surface material has a part that is easily delaminated.

It can be judged that the fabric does not have a monolayer structure, when some layer can be easily peeled off from the fabric, or when the type of the constituent fibers on one main surface of the fabric and the type of the constituent fibers on the other main surface is not the same.

The surface material (10) of the present invention is flexible because of containing a fabric (particularly, a nonwoven fabric in which all constituent fibers are randomly entangled), and is excellent in heat moldability. It is to be noted that the surface material (10) provided with a fabric (particularly, a nonwoven fabric) in which all of the constituent fibers are randomly entangled is more flexible, and is more excellent in heat moldability.

The constituent fibers of the fabric are, for example, a polyolefin-based resin (e.g., polyethylene, polypropylene, polymethylpentene, a polyolefin-based resin having a structure in which a part of a hydrocarbon is replaced with a halogen such as a cyano group or fluorine or chlorine), a styrene-based resin, a polyether-based resin (e.g., polyether ether ketone, a modified polyphenylene ether, an aromatic polyether ketone, or the like), a polyester-based resin (e.g., polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polycarbonate, polyarylate, wholly aromatic polyester resins, polyamide-imide resins, polyamide-based resins (e.g., aromatic polyamide resins, aromatic polyether amide resins, nylon resins, etc.), resins having a nitrile group (e.g., Polyacrylonitrile and the like), urethane-based resins, epoxy-based resins, polysulfone-based resins (e.g., polysulfone, polyether sulfone, and the like), fluorine-based resins (e.g., polytetrafluoroethylene, polyvinylidene fluoride, and the like), cellulose-based resins, polybenzimidazole resins, acrylic resins (e.g., polyacrylonitrile-based resins obtained by copolymerizing acrylic esters or methacrylic esters, etc., modaacrylic resins obtained by copolymerizing acrylonitrile with vinyl chloride or vinylidene chloride, and the like), and the like can be constituted using known resins.

Note that these resins may be made of any of a linear polymer or a branched polymer, and the resin may be a block copolymer or a random copolymer, and there is no particular limitation on the presence or absence of the steric structure or crystallinity of the resin. Further, it may be a mixture of multi-component resin. Further, it may be a fiber prepared by kneading a pigment or a fiber which is dyed.

When flame retardancy is required for the surface material (10), it is preferable that the constituent fibers of the fabric contain a flame-retardant resin. As such a flame retardant resin, for example, modaacrylic resin, vinylidene resin, polyvinyl chloride resin, polyvinylidene fluoride resin, novoloid resin, polychlal resin, polyester resin obtained by copolymerizing a phosphorus compound, halogen-containing monomer copolymerized acrylic resin, aramid resin, such as a resin kneaded with a flame retardant halogen-based or phosphorus-based or metal compound-based. Further, it may be a surface material (10) on which a flame retardant is supported by using a binder or the like.

The constituent fibers can be obtained by known methods, for example, melt spinning, dry spinning, wet spinning, direct spinning (melt blowing, span bonding, electrostatic spinning, etc.), extraction of fibers with thin fiber diameters by removing one or more resin components from composite fibers, and decomposition of fibers to obtain split fibers.

The constituent fibers may be made of a single type of resin or may be made of a plurality of kinds of resins. The fibers composed of a plurality of types of resins may be generally referred to as composite fibers, for example, in the form of a sheath-core type, an island-sea type, a side-by-side type, an orange type, a bimetallic type, or the like.

Further, the constituent fibers may contain a deformed cross-section fiber other than a substantially circular fiber or an oval fiber. Incidentally, as the deformed cross-sectional fiber is may be a hollow shape, polygonal shape such as a triangular shape, alphabet character-type shape such as a Y-shape, irregular shape, multileaf shape, symbol-type shape such as an asterisk shape or a fiber having cross-sectional shape of combination with a plurality of these shapes.

When the fabric contains heat fusible fibers as constituent fibers, it is preferable to impart strength and morphological stability to the fabric by thermally fusing the fibers together, thereby suppressing the occurrence of shaving and unintentional fluffing. Such a heat fusible fiber may be a heat-fusible fiber of all-fusion type, or may be a heat fusible fiber of a partially fusible type such as the composite fiber described above. As a component which exhibits heat fusibility in the heat fusible fiber, for example, a heat fusible fiber containing a low melting point polyolefin-based resin or a low melting point polyester-based resin can be appropriately selected and used.

When the fabric contains crimpable fibers, stretchability is increased and followability to a mold is excellent and preferable. As such a crimpable fiber, for example, a crimp fiber that expressed the crimp of a latent crimpable fiber or a fiber having a crimp can be used. Further, it may contain a latent crimpable fiber in which a fabric exhibits crimp by heating.

When the fabric is a fiber web or a nonwoven fabric, it can be prepared by, for example, a dry method in which fibers are entangled by subjecting the above-mentioned fibers to a card device or an air-laying apparatus, a wet method in which the fibers are dispersed in a solvent and the fibers are entangled into a sheet and method in spin and collect fibers by using a direct spinning method (a meltblowing method, a spunbond method, an electrostatic spinning method, a method in which a spinning liquid and a gas stream are discharged in parallel and spun (for example, a method disclosed in No. JP2009287138A).

The constituent fibers of the prepared fiber web can be entangled and/or integrated to prepare a nonwoven fabric. As a method of entangling and/or integrating the constituent fibers together, for example, a method of entangling by a needle or a water flow, a method of bonding and integrating the constituent fibers together by a binder or an adhesive fiber by subjecting the fiber web to a heat treatment, or the like can be mentioned.

The method of the heat treatment can be selected as appropriate; for example, a method of heating or pressurizing with heat by a roll, a method of heating by a heater such as an oven dryer, a far-infrared heater, a dry heat dryer or a hot air dryer, or a method of heating by irradiating infrared rays under no pressure, or the like can be used.

When the fabric is a woven fabric or a knitted fabric, a woven fabric or a knitted fabric can be prepared by weaving or knitting the fibers prepared as described above.

In addition to the fiber web, a nonwoven fabric, woven fabric or a knitted fabric may be subjected to a method of entangling and/or integrating the above-described constituent fibers with each other.

Although there is no particular limitation on the fineness of the constituent fibers of the monolayer fabric (1), it can be 0. 1 dtex or more, can be 0. 5 dtex or more, and can be 1. 0 dtex or more to improve the appearance-retentioning property.

On the other hand, it can be 100 dtex or less, can be 50 dtex or less, can be 30 dtex or less, and can be 10 dtex or less so that a surface material (10) excellent in moldability can be prepared.

Further, although the fiber length of the constituent fibers of the monolayer fabric (1) is not particularly limited, it can be 20 mm or more, can be 25 mm or more, and can be 30 mm or more to improve the appearance-retentioning property. On the other hand, when the fiber length is more than 110 mm, a fiber mass tends to be formed at the time of preparation of the monolayer fabric (1), and it may be difficult to prepare a surface material (10) having excellent moldability, so that it is preferably 110 mm or less, and can be 70 mm or less. “Fiber length” refers to values measured according to JIS L1015 (2010), 8.4. 1c) direct method (C method).

Various configurations of the monolayer fabric (1), for example, a thickness, a basis weight and the like, are not particularly limited and are appropriately adjusted.

The thickness of the monolayer fabric (1) can be 500-50000 can be 1000-3000 and can be 1100-1900 Note that the thickness of the monolayer fabric (1) in the present invention refers to a length between an end point (A) and an end point (B) in a line segment (shown as X in the drawing), which is calculated under the item described later (Method for Confirming the Present Mode of the binder layer).

Also, the basis weight of the monolayer fabric (1) can be, for example, from 50 to 500 g/m², from 80 to 300 g/m², and from 100 to 250 g/m². Incidentally, the basis weight in the present invention refers to the weight per 1 m² in a surface (main surface) having the widest area of the measuring object.

Although the binder usable in the present invention is chosen as appropriate, for example, polyolefin based resin (modified polyolefin etc.), ethylene-acrylate copolymers such as ethylene-ethylacrylate copolymer, various rubbers and their derivatives (styrene-butadiene rubber (SBR), fluorine rubber, ethylene-propylene-diene rubber (EPDM), etc.), cellulose derivatives (carboxymethyl cellulose (CMC), hydroxyethyl cellulose, etc.), polyvinyl alcohol (PVA), polyvinyl butyral (PVB), Polyvinylpyrrolidone (PVP), polyurethane, epoxy resin, polyvinylidene fluoride (PVdF), vinylidene fluoride-hexafluoropropylene copolymer (PVdF-HFP), acrylic resin (e.g., versatile vinyl ester copolymer acrylic resin), and the like can be used. When an acrylic resin is employed as a binder, it is preferable to provide a surface material (10) having excellent followability to a mold for moderately softening during thermoforming.

The binder may contain, for example, an additive such as a flame retardant, a perfume, a pigment, an antibacterial agent, an antifungal material, a photocatalyst particulate, an inorganic particle such as silica, a hollow particle such as a particle to be heated and foamed or an already foamed particle, an emulsifier, a dispersant, or a surfactant.

The basis weight of the binder contained in the monolayer fabric (1) is appropriately selected to provide a surface material (10) satisfying the configuration of the present invention. Specifically, the weight of the binder may be 2 g/m² or more. The weight of the binder can be less than or equal to 50 g/m², less than or equal to 30 g/m², and less than or equal to 20 g/m².

The surface material (10) according to the present invention is characterized in that one or more layers of binder (2) is present in the monolayer fabric (1). In other words, there is the binder layer (2) only in the inner side of one main surface in the monolayer fabric (1) and in the inner side of the other main surface in the monolayer fabric (1).

Here, “the presence of the binder layer (2) only in the inner side of one main surface of the monolayer fabric (1)” and “the presence of the binder layer (2) only in the inner side of the other main surface of the monolayer fabric (1)” mean the presence of the binder layer (2) without contacting either one main surface and the other main surface in the optical micrograph of the cross-section of the monolayer fabric (1) taken in the later-described (Method for confirming the binder layer).

The binder layer (2) present in the monolayer fabric (1) can be judged by subjecting it to the following measurement method.

(Method for Confirming the Binder Layer)

1. A sample (shape: square or rectangle) is collected from a fabric (e.g., a monolayer fabric (1) or a surface material (10)) to be measured. 2. A dyeing solution capable of dyeing a binder contained in the measurement target (e.g., Kayastein Q (manufactured by Nippon Kayaku Co., Ltd.) or the like) is prepared. 3. Dye the binder contained in the sample using the dyeing solution. 4. The dyed sample is cut in the thickness direction, the inkjet printing glossy paper (12) is superimposed on both main surfaces of the cut sample, and the sample is pinched and held in the thickness direction by the glass plate (11) from above the inkjet printing glossy paper (12) and fixed (the pressure applied in the thickness direction of the sample by the glass plate (11): 20 g/cm²).

Then, in this state, a cross-section of the sample after cutting is photographed by a 30 x optical microscope. In addition, an optical micrograph is taken so that the entire thickness direction of the cross-section of the dyed sample is within the vertical range in the optical micrograph. Further, in the cross-section, the area of the square which has a one side as line segment indicating the length of the thickness direction of the sample is taken to fit in the optical micrograph.

Note that the binder layer (2) is a layer formed by a continuous presence of the binder so as to cross the lateral direction (a direction perpendicular to the thickness direction of the sample cross-section) of the above-mentioned square area in the optical micrograph.

Shown in the optical micrograph, when the one or more layers of binder (2) is present only in the inner side of one main surface in the sample after dyeing and present only in the inner side of the other main surface in the sample after dyeing, the measurement target satisfies the configuration of the present invention. In other words, in described later (a method for confirming the present mode of a binder layer), when W and Y and Z are longer than 0 as in FIG. 1, the measurement target satisfies the configuration of the present invention.

In addition, when a pressure is applied in the thickness direction of the monolayer fabric (1) comprising the binder layer (2) according to the present invention, the portion of the binder layer (2) is a highly rigid area, where the fibers that make up said area are integrated with binder, so that it is a portion that is less likely to be deformed in the thickness direction and less likely to be thinner than other portion where the binder layer (2) does not existing.

In addition, the number of binder layers (2) possessed by the monolayer fabric (1) may be appropriately adjusted and a plurality of layers may be used. However, it is preferable to have only one binder layer (2) to be able to easily provide a surface material (10) having a main surface which is excellent feeling in touch and hardly causes fiber dropouts. Incidentally, the surface material (10) according to the present invention, in addition to the binder layer (2), may have a binder portion having a band-like form without forming a layered form without one subsequent presence.

The thickness of the binder layer (2) can be appropriately adjusted, but is smaller than the thickness of the monolayer fabric (1) shown in the above-described optical micrograph, and can be 200 to 1000 μm, and can be 300 to 500 Note that the thickness of the binder layer (2) can be determined by the following method.

(Method for Measuring the Thickness of a Binder Layer)

1. A line segment connecting the two main surfaces of the monolayer fabric (1) shown in the above-mentioned optical micrograph at the shortest distance is drawn on the optical micrograph. It is to be noted that an end point (a contact point between one main surface and a line segment) on one main surface side of the monolayer fabric (1) in the line segment is defined as an end point (A), and an end point (a contact point between the other main surface and the line segment) on the other main surface side of the monolayer fabric (1) in the line segment is defined as an end point (B). Then, the length between the end point (A) and the end point (B) in the line segment is defined as the thickness (unit: μm) of the monolayer fabric (1). Note that, in the figure, the thickness of the monolayer fabric (1) is illustrated as X. 2. The intersection point (a) of the line segment with the contour on one main surface side in one of the binder layer (2) in the optical micrograph and the intersection point (b) of the line segment with the contour on the other main surface side in said binder layer (2) are drawn on the optical micrograph. The length between the intersection point (a) and the intersection point (b) in the line segment is defined as the thickness (unit: μm) of the binder layer (2). In the drawing, the thickness of the binder layer (2) is shown as W.

Note that, although the percentage of the thickness of the binder layer (2) in the thickness of the monolayer fabric (1) can be appropriately adjusted, it can be in the range of 5% to 80%, can be in the range of 10% to 60%, and can be in the range of 20% to 30%. Note that the percentage can be determined by calculating a percentage of the thickness of the binder layer (2) occupying the thickness of the monolayer fabric (1).

It is possible to appropriately adjust how much of the binder layer (2) is present in the inner side from the main surface in the monolayer fabric (1). Note that the present mode of the binder layer (2) can be confirmed by the following method.

(Method for Confirming the Present Mode of the Binder Layer)

1. The length (X) between the end point (A) and the end point (B) in the line segment, the length (denoted by Y in the figure, it means the depth from one main surface to the existence of the binder layer (2)) between the end point (A) and the intersection point (a) in the line segment, and the length (denoted by Z in the figure, it means the depth from the other main surface to the existence of the binder layer (2)) between the end point (B) and the intersection point (b) in the line segment, drawn in the above (Method for Measuring the Thickness of a Binder Layer) are determined. 2. Calculate the value of 100×Y/X (unit: %). From the result of the calculation, it can be determined that a binder layer (2) is present in a range of the calculated value (unit: %) or more in the thickness direction of the monolayer fabric (1) from one main surface. 3. Calculate the value of 100×Z/X (unit: %). From the result of the calculation, it can be determined that a binder layer (2) is present in a range of the calculated value (unit: %) or more in the thickness direction of the monolayer fabric (1) from the other main surface.

In the surface material (10) satisfying the constitution of the present invention, the calculated value of 100×Y/X and the calculated value of 100×Z/X are both larger than 0%. The calculated value can be appropriately adjusted as long as it satisfies the configuration of the present invention, but can be 5% or more, can be 7% or more, can be 10% or more, and can be 15% or more. The upper limit of each calculated value can be appropriately adjusted, but can be 73% or less, 70% or less, and 60% or less.

Note that the surface material (10) according to the present invention satisfies the following configuration.

-   -   W, X, Y, Z are all greater than 0.     -   The sum of the calculated value of 100×Y/X and the calculated         value of 100×Z/X is less than 100%.     -   X is the sum of W+Y+Z.

The physical properties of the surface material (10), such as the weight and thickness, can be appropriately adjusted to achieve the object of the present invention, for example, the weight can be 140 to 300 g/m², can be 150 to 260 g/m², and can be 160 to 250 g/m². Also, the thickness can be between 500 and 50000 μm, between 1000 and 3000 μm, and between 1100 and 1900 μm.

The value of the dynamic friction coefficient of the main surface (in the case the surface material (10) composed only of the monolayer fabric (1) provided with the binder layer (2), it is the main surface of the monolayer fabric (1)) can be 1.2 μk or less, can be 1.1 μk or less, and can be 1.0 μk or less. The dynamic friction coefficient can be obtained by the following measurement method.

(Measuring Method of Dynamic Friction Coefficient)

Dynamic frictional coefficients are values measured using a surface property tester (Tribostation Type32, manufactured by Shinto Scientific Co., Ltd.). A sample (63.5 mm×about 130 mm) taken from the fabric to be measured is wrapped around a planar indenter without slack, fixed by clamps at both ends, and set on a glass plate. Thereafter, a planar indenter is brought into contact with the exposed main surface of the sample set on the glass plate, and a load of 50 g is applied in the thickness direction of the sample by the planar indenter. Then, the sample is moved at a speed of 100 mm/min by 60 mm in a direction which is perpendicular to the direction of loading while the load is applied. Calculate the dynamic friction coefficient μk (the ratio between the measured dynamic friction value and the force acting perpendicular to the main surface of the test piece) from the measured dynamic friction value (the force resisting when continuing to slide on one surface) measured during that time.

Surface roughness (SMD) of the main surface of the surface material (10) and the average friction coefficient (MIU) and the fluctuations of average frictional coefficient (MMD) is appropriately adjusted to realize a surface material (10) having excellent tactile feeling.

The surface roughness (SMD) is a value measured using a surface tester (KES-FB4, manufactured by Katotech Corporation), and means the mean deviation (average deviation of surface roughness data) measured by setting a sample (20 cm square) taken from the surface material (10) with a load of 400 g on the tester, applying a load of 10.0 g to the roughness contactor (0.5 mm wire, contact surface width: 5 mm), and moving the sample at a velocity of 1 mm/sec., and its unit is

The surface roughness (SMD) is preferably 2.3 μm or more to adjust the surface material (10) capable to make people feel raised feeling on the surface. Although the upper limit of the value of the surface roughness (SMD) is not particularly determined, since there is a fear of decreasing tactile feeling by a strong feeling of surface irregularities on the surface, If the value was excessively high, so the surface roughness (SMD) is 4.5 μm or less it is desirable.

The average coefficient of friction (MIU) of the main surface of the surface material (10) is an index indicating the flexibility of the main surface. The average coefficient of friction (MIU; frictional coefficient) is an average value of coefficient of friction μ between 20 mm (average value of μ in a distance of 20 mm) measured using a surface tester (KES-FB4), and means an average value measured by setting a sample (20 cm square) taken from the surface material (10) in the tester with a load of 400 g, applying a load of 50 g to the frictionator (5 mm×5 mm), and moving the sample at a velocity of 1 mm/sec.

The average friction coefficient (MIU) is preferably 0.19 or more. On the other hand, if the value of the average friction coefficient (MIU) was too large, friction resistance is too high and may impair the tactile feeling, so it is preferably 1.6 or less.

The average friction coefficient (MMD) of the main surface of the surface material (10) is an index indicating the uniformity of the main surface. The fluctuations of average frictional coefficient (MMD) mean the average deviation in measuring the average coefficient of friction (MIU).

The upper limit of the fluctuations of average frictional coefficient (MMD) can be 0.01 or less, and the lower limit can be 0.005 or more, and can be 0.008 or more.

A monolayer fabric (1) with one or more layers of binder (2) according to the present invention may be a surface material (10) alone, but may be a surface material (10) formed by laminating a constituent member such as another fabric, a porous body, a film, or a foam. At this time, it is laminated on the surface material (10) so that the main surface of the monolayer fabric (1) is exposed.

Surface material (10) can be subjected to the thermoforming process, or it can be subjected to various secondary step: such as punching out a shape in accordance with the application and use, such as a step of adjusting the smoothness of the thickness and the surface such as a reliant press treatment, then to a thermoforming step.

Next, a method of manufacturing the surface material (10) of the present invention will be described. Description of the points having the same configuration as the above-described items is omitted.

Although the method of manufacturing the surface material (10) according to the present invention can be appropriately selected, as an example, a method of manufacturing a surface material (10), comprising:

“(1) preparing a monolayer fabric, (2) preparing binder liquid comprising binder and solvent and/or dispersion medium of the binder, (3) applying the binder liquid to one main surface of the monolayer fabric, (4) applying the solvent and/or the dispersion medium to the one main surface of the monolayer fabric, and (5) removing the solvent and/or the dispersion medium from the monolayer fabric.”

Step (1) will be described.

As a monolayer fabric (1), for example, a fibrous web or a nonwoven fabric, or a sheet-like fabric such as a woven fabric or a knitted fabric is prepared. Note that the fineness and the fiber length of the constituent fibers in the monolayer fabric (1), and the thickness and the basis weight of the monolayer fabric (1) can be appropriately adjusted.

The process (2) will be described.

The type of binder can be appropriately selected. In addition, although the type of the solvent or the dispersion medium can be appropriately selected and, for example, water or the like can be employed, it is preferable to employ a solvent in which the binder can be dissolved and the monolayer fabric (1) is not dissolved, or to employ a dispersion medium in which the binder can be dispersed and the monolayer fabric (1) is not dissolved, so that the binder liquid can be suitably applied to the monolayer fabric (1). Further, the concentration and viscosity of the binder occupying the binder liquid are appropriately adjusted be able to apply to the surface material (10) according to the present invention. Further, it may be a binder liquid to which a thickener, a defoaming agent, or the like is added to be able to apply to the surface material (10) of the present invention.

Step (3) will be described.

Although a method of applying a binder liquid to one main surface in the monolayer fabric (1) can be appropriately selected, a method of spraying or applying the binder liquid to one main surface of the monolayer fabric (1) as it is or in a frothed state using a spray, an impregnation roll or the like, a method of immersing one main surface of a monolayer fabric (1) in a binder liquid, or the like can be employed. Note that the amount of the binder liquid to be applied to one main surface of the monolayer fabric (1) is appropriately adjusted to be able to provide the surface material (10) according to the present invention. Also, the number of times of applying the binder liquid to one main surface of the monolayer fabric (1) may be one or more times.

Step (4) will be described.

In the above-described step (3), a solvent and/or a dispersion medium which can constitute a binder liquid are applied to the main surface to which the binder liquid was applied, of the monolayer fabric (1). In the present process of the present invention, a binder liquid present on one main surface is then pushed from said one main surface to the inner side of the fabric by the solvent and/or the dispersion medium containing no binder to be applied to, so that there is no binder liquid on the main surface. Note that a solvent obtained by removing the binder component from the binder liquid and/or a dispersion medium obtained by removing the binder component from the binder liquid may be used as a solvent and/or a dispersion medium. Such a solvent and/or a dispersion medium may contain a thickener, a defoaming agent, and the like.

The amount of the solvent and/or the dispersion medium to be applied to one main surface of the monolayer fabric (1) is appropriately adjusted to be able to provide the surface material (10) according to the present invention. The number of times of applying a solvent and/or a dispersion medium to one main surface of the monolayer fabric (1) may be one or more times. Also, a solvent and/or a dispersion medium may be similarly applied to the other main surface of the monolayer fabric (1).

When the amount of the solvent and/or the dispersion medium to be applied is adjusted to a small amount, it is easy to realize a surface material (10), wherein a binder layer (2) is present in a shallow portion in an inner side from one main surface of a monolayer fabric (1). Further, when the amount of the solvent and/or the dispersion medium to be applied is adjusted to a large amount, it is easy to realize a surface material (10), wherein a binder layers (2) is present in a deep portion in an inner side from one main surface of a monolayer fabric (1). In other words, by adjusting the amount of the solvent and/or the dispersion medium to be applied to one main surface of the monolayer fabric (1), it is possible to adjust the present mode of the binder layers (2) in the monolayer fabric (1).

It is preferable to apply to a solvent and/or a dispersion medium after the binder liquid applied to one main surface of the monolayer fabric (1) before dries so that the above-described effect is efficiently exhibited.

Step (5) will be described.

A method of removing the solvent or the dispersion medium can be appropriately selected, but the solvent or the dispersion medium can be evaporated and removed by, for example, heating by being supplied to a heater such as an oven dryer, a far-infrared heater, a dry heat dryer, or a hot air dryer, or by being left standing in an atmosphere at room temperature or in reduced pressure. The heating temperature at the time of removing the solvent or the dispersion medium is a temperature at which the solvent or the dispersion medium can volatilize. And the upper limit of the heating temperature is adjusted so that the constituent components of the monolayer fabric (1), the function of the binder and the like are not unintentionally lowered. Also, if particles which are subjected to heating and foamed are provided, the particles may be foamed by this step.

Through the above-described process, a surface material (10) satisfying the configuration according to the present invention can be prepared. The interior material can be prepared by subjecting the surface material (10) to thermoforming means. Before and after being provided to the thermoforming means, the surface material (10) or the interior material may be subjected to secondary processing such as punching out, cutting, or giving a three-dimensional shape.

EXAMPLES

Hereinafter, the present invention will be specifically described by way of Examples, but these do not limit the scope of the present invention.

(Preparation of a Monolayer Fabric)

Using 100% of the dyed polyester fibers (fineness: 1.3 dtex, fiber length: 51 mm), a fibrous web was formed by opening by a curding machine. Thereafter, needle punching was performed from one side at a needle density of 400 needles/cm², and then the resultant was subjected to a hot roll (roll heat temperature: 150° C.) to prepare a monolayer nonwoven fabric (basis weight: 190 g/m², thickness: 1960 μm).

(Preparation of Binder Liquid)

A binder liquid prepared by mixing the following formulations was prepared.

Thickener A (solid concentration: 0.36 parts by mass) . . . 24 parts by mass Thickener B (solid concentration: 0.28 parts by mass) . . .1 part by mass Antifoaming agent (solid concentration: 0.07 parts by mass) . . . 0.5 parts by mass Acrylic resin emulsion (solid concentration: 4.5 parts by mass) . . . 10 parts by mass Silicone-based resin emulsion (solid concentration: 0.96 parts by mass) . . . 3 parts by mass 25% concentration ammonia water . . . 1 part by weight Water . . . 60.5 parts by mass

Note that the binder component contained in the present binder liquid was only an acrylic resin which contained in an acrylic resin emulsion, and the present binder liquid was an emulsion liquid of binder particles.

(Preparation of Liquid Containing Dispersion Medium)

A Liquid Containing Dispersion Medium obtained by mixing the following formulations was prepared.

  Thickener A (solid concentration: 0.39 parts by mass) . . . 26 parts by mass Antifoaming agent (solid concentration: 0.07 parts by mass) . . . 0.5 parts by mass 25% concentration ammonia water . . . 1 part by weight Water . . . 72.5 parts by mass

Note that the binder component was not contained in the Liquid Containing Dispersion Medium.

Comparative Example 1

The monolayer nonwoven fabric was dried in a tenter dryer at a temperature of 180° C. Thereafter, the surface material (basis weight: 190 g/m², thickness: 1960 μm) was prepared by cooling by dissipating heat.

Comparative Example 2

The binder liquid was applied only to the main surface of the monolayer nonwoven fabric opposite to the main surface side to which the needling was subjected, using a cylinder. By drying a monolayer nonwoven fabric to which the binder liquid was applied with a tenter dryer at a temperature of 180° C., then the constituent fibers were bonded and fixed to each other by an acrylic resin contained in the binder liquid, and the dispersion medium was removed.

Thereafter, the surface material (basis weight: 197 g/m², thickness: 1870 μm) was prepared by cooling by dissipating heat.

Example 1

The binder liquid was applied only to the main surface of the monolayer nonwoven fabric opposite to the main surface side to which the needling was subjected, using a cylinder. Further, the Liquid Containing Dispersion Medium was applied the same volume as the binder liquid to the main surface of the monolayer nonwoven fabric opposite to the main surface side to which the binder liquid was applied, using a cylinder. By drying a monolayer nonwoven fabric to which the binder liquid and the Liquid Containing Dispersion Medium were applied with a tenter dryer at a temperature of 180° C., then the constituent fibers were bonded and fixed to each other by an acrylic resin contained in the binder liquid, and the dispersion medium was removed. Thereafter, the surface material (basis weight: 197 g/m², thickness: 1830 μm) was prepared by cooling by dissipating heat.

Example 2

A surface material (basis weight: 197 g/m², thickness: 1840 μm) was prepared in the same manner as in Example 1, except that the amount of the Liquid Containing Dispersion Medium added was larger than that in Example 1.

Example 3

A surface material (basis weight: 197 g/m², thickness: 1820 μm) was prepared in the same manner as in Example 2, except that the amount of the Liquid Containing Dispersion Medium added was larger than that in Example 2.

An optical micrograph of a cross-section of each surface material prepared as described above is illustrated in FIG. 2-FIG. 6. The white plate-like object present on both main surfaces of the surface material in each optical micrograph is inkjet printing glossy paper. In addition, in order to make it easy to understand the existence mode of the binder layer, a schematic diagram of showing an approximate relationship of each length is also shown on the left side of the optical micrograph. Since the surface material prepared in Comparative Example 1 (FIG. 2) does not have a binder layer, so it does not have portions corresponding to W, Y, and Z. Further, since the surface material prepared in Comparative Example 2 (FIG. 3) has a binder layer which contact with one main surface, so it does not have a portion corresponding to Y.

Table 1 summarizes the various configurations and evaluation results of each surface material prepared as described above. In addition, “fiber shedding property” and “sensory evaluation” in Table 1 were measured by the method described below. Note that, items without binder layer were not subject to measurement, so “-” was described in the table.

(Method of Measuring Sensory Evaluation)

The raised feeling and smoothness felt when a person touched the main surface of the surface material was evaluated, and said main surface derived from a main surface of the monolayer nonwoven fabric wherein it is opposite side to which the needling was subjected. The measurement was carried out by the same 10 persons for each surface material. Then, the total value of each item was calculated. The larger the total value of raised feeling, the better raised feeling of the main surface, and the larger the total value of the smoothness, the better the smoothness of the main surface.

Raised feeling: feeling . . . 2 points, feeling slightly . . . 1 point, do not feel . . . 0 point Smoothness: feeling . . . 2 points, feeling slightly . . . 1 point, feeling roughness and feeling no smoothness . . . 0 points

(Evaluation Method of Fiber Shedding Property)

In accordance with JIS K7204: 1999 (Abrasion Test Methods with Abrasion Rings-Plastic), the fiber shedding properties of the main surface of the surface material was evaluated, and said main surface derived from a main surface of the monolayer nonwoven fabric wherein it is opposite side to which the needling was subjected. Incidentally, the friction tester, the rotational friction speed, the friction ring used, the load applied to the friction ring, the number of frictions were as follows.

(1) Friction tester: Rotary Ablation Tester, Toyo Seiki Co., Ltd. (2) Rotating friction speed: 70 r/min (3) Friction ring No.: CS-10 (4) Load applied to the friction ring: 4.9 N (5) Number of frictions: 100 times

The portion, which had been subjected to the friction ring treatment, of the main surface was visually observed and evaluated according to the following criteria.

Grade 3: Only slight fiber dropouts was observed. Grade 2: A greater number of fiber dropouts were observed than in Grade 3 results.

Therefore, the surface material which has been evaluated in the Grade 3 has a main surface on which fiber dropouts is harder to occur than the surface material which has been evaluated in the Grade 2.

TABLE 1 Comparative Comparative Example 1 Example 2 Example 1 Example 2 Example 3 Basis Weight (g/m²) 190 197 197 197 197 Thickness, X (μm) 1960 1870 1830 1840 1820 Y (μm) — 0 140 220 310 Thickness Of The Binder Layer, W (μm) — 415 360 400 440 Z (μm) — 1455 1330 1220 1070 100 * Y/X (%) — 0.0 7.7 12.0 17.0 100 * Z/X (%) — 77.8 72.7 66.3 58.8 Value Of The Dynamic Friction Coefficient (μk) 0.92 1.21 0.99 0.91 0.87 MIU (μm) 0.199 0.186 0.208 0.203 0.196 MMD 0.0085 0.0073 0.0083 0.0086 0.0081 SMD 2.496 1.957 2.353 2.413 2.519 Sensory Evaluation Raised Feeling 20 7 12 14 16 Smoothness 6 15 16 15 15 Fiber Shedding Property 2 3 3 3 3

From the results of comparing the comparative example and the examples, the surface material satisfying the configuration according to the present invention has a main surface which is excellent feeling in touch and is resistant to fiber shedding

INDUSTRIAL APPLICABILITY

The surface material of the present invention is a surface material capable of preparing various interior materials. In particular, it is a surface material capable of preparing interior materials such as vehicle ceilings, pillar garnishes, doors, instrument panels, steering wheels, shift levers, console boxes, tonno covers, luggage floors, luggage sides, and the like.

REFERENCE SIGNS LIST

-   10: Surface material -   1: Monolayer fabric -   2: Binder Layer -   11: Glass plate -   12: Inkjet printing glossy paper -   W: Thickness of the binder layer -   X: Thickness of the monolayer fabric -   Y: Depth from one main surface to the presence of the binder layer -   Z: Depth from the other main surface to the presence of the binder     layer -   A: End point on one main surface side of the monolayer fabric     (contact point between one main surface and the line segment) on the     line segment, connecting the two main surfaces of the monolayer     fabric at the shortest distance -   B: End point on the other main surface side of the monolayer fabric     (contact point between the other main surface and the line segment)     on the line segment, connecting the two main surfaces of the     monolayer fabric at the shortest distance -   a: Intersection of line segment and the contour of one main surface     side of the binder layer -   b: Intersection of line segment and the contour of the other main     surface side of the binder layer 

1. A surface material comprising a binder and a monolayer fabric, the monolayer fabric having a first main surface and, on a side opposite the first main surface, a second main surface, wherein one or more layers of said binder are present only in an inner side of the first main surface of said monolayer fabric and only in an inner side of the second main surface of said monolayer fabric.
 2. A method for manufacturing a surface material according to claim 1, comprising: (1) preparing a monolayer fabric, (2) preparing a binder liquid comprising a binder, and a solvent and/or a dispersion medium for the binder, (3) applying the binder liquid to one main surface of the monolayer fabric, (4) applying the solvent and/or the dispersion medium to the one main surface of the monolayer fabric, and (5) removing the solvent and/or the dispersion medium from the monolayer fabric. 